Single and double storey extensions in Romford. Trusted, professional, 30+ years' hands-on experience.
GS Renovation designs and builds extensions across Romford, where the interwar semis and modern homes of RM1 sit on the generous plots typical of Havering's suburbs. With over 30 years of local building experience, we take on rear, side-return and wrap-around projects, from foundations through to a fully finished, decorated space.

The deep back gardens common to Romford's 1930s semis give real room to extend, which is why single storey rear and wrap-around extensions are so popular in RM1. We dig and pour the foundations, lay the groundworks, and build the shell, then install the steel beams that let us open the new addition into the existing kitchen or reception. Roof works, glazing and the full fit-out follow, all handled by one team.
Double storey extensions suit these houses too, adding a bedroom and a larger kitchen-diner while making the most of the wide plots. Because the properties are semi-detached, we consider the shared boundary from the outset, serve any and set the design to respect your neighbour's light and outlook. Everything structural is signed off by Havering building control as the work proceeds.
Not every Romford extension needs a planning application. Many single storey rear projects fall under permitted development, provided they stay within the size, height and boundary limits, which the generous RM1 plots often allow. Where a design goes beyond those rights, or where the house sits in a spot with restrictions, we make a full planning application to Havering Council and manage the drawings and submission for you.
Whichever route applies, building regulations always govern the structure, so foundations, beams, insulation and drainage are inspected regardless of the planning position. We advise honestly at the start on which path your property falls under, so there are no surprises. This clarity matters most on the interwar semis, where a wrap-around can quickly cross from permitted development into needing full permission.
Romford homeowners choose GS Renovation because we manage the whole extension, from foundations and steel to roof and decoration, under one roof. We advise clearly on whether your project is permitted development or needs a planning application to Havering Council, handle party wall matters on semi-detached boundaries, and keep building control informed. Over 30 years in RM1 backs every project.
We loved working with George and Ibrahim and would highly recommend them. They have done splendid job on our new kitchen refurb which including new…
Really happy with the quality of remedial works carried out by George in putting other previous tradesman work right. He was very helpful, honest and…
He was very very good. He just got on with the job and we was beey pleased with the result. He Also cleaned everything away when he finished. Will…
FAQ
Very, and deliberately so. Quoting house extensions low to win a Romford job and correcting it later is the commonest complaint homeowners have about builders, and it is not how GS Renovation operates. We survey the RM1 address, itemise, and stand behind the total. Anything genuinely unforeseen is costed and agreed before further work. Ring 07472 424 226 and ask GS Renovation for the RM1 breakdown before you compare it with another Havering quotation for house extensions. As a rough guide, house extensions in London typically starts from roughly £40,000 for a single-storey rear extension and rises with size and specification (indicative London ranges, MyBuilder and Checkatrade, 2026). Your figure depends on the size, specification and condition of the property, which is why we survey before quoting.
More than in inner London, because the gardens are generally longer. Houses around Romford often have space for a substantial rear extension without losing the whole garden, and side space as well on the semi detached stock. What limits it is usually daylight to the existing rooms and what permission allows rather than the plot. The design starts from what the house needs, not from the maximum footprint.
Where a bedroom is needed as well as living space, frequently yes. Building up as well as out at your Romford property adds far more floor area for a modest increase in foundation and roof work, though it is more likely to need planning permission and affects the neighbour's outlook more directly. The structural work is greater because loads carry through to the foundations.
The Party Wall etc. Act is usually engaged and notice is served first. Excavating close to a neighbouring structure at your Romford property brings the work within the Act even where nothing touches the boundary wall. The owner serves notice, and where consent is not given surveyors are appointed and an award follows. The foundation design may be adjusted to suit what the award permits.
At a junction designed to shed water and stay watertight for the long term. Where a Romford extension meets the existing house, the abutment is flashed into the original brickwork and the falls are set so water runs away from the joint. A shallow or badly detailed junction is the first place a flat roof leaks. That detail is specified rather than left to the roofer on the day.
Every Service, One Team
The same trusted team, 30+ years' hands-on experience and free, no-obligation quotes apply to every GS Renovation service in Romford. Explore what else we do locally:
Same Service, Nearby Areas
We carry out house extensions across Romford and the surrounding areas. Explore a nearby location:
Free, no-obligation quote for house extensions in Romford. Rated 4.9 from 31 reviews on MyBuilder, fully insured, and building control handled for you.